Area Forecast Discussion
Issued by NWS Sterling, VA
Issued by NWS Sterling, VA
715 FXUS61 KLWX 200637 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 137 AM EST Thu Nov 20 2025 .SYNOPSIS... Wedging high pressure will keep things dry and cloudy through Thursday night. Low pressure approaching from the Ohio and mid- Mississippi River Valleys will bring another round of rain to the region Friday into Friday night. A cold front will swing through the area early Saturday with high pressure building over the central Appalachians Sunday into Monday. Another wave of low pressure and front look to cross the area Tuesday into the middle part of next week. && .NEAR TERM /THROUGH TONIGHT/... High pressure will remain firmly wedged down the east side of the Appalachians through tonight. This will result in abundant cloud cover, cool daytime temperatures, and relatively milder overnight low temperatures. Although a few sprinkles or patchy drizzle can`t be ruled out at times, it is expected to be mostly rain free. Areas of fog are possible tonight given lingering low-level moisture and light onshore flow going calm. Fog would be most widespread (and possibly dense) in areas where clouds break. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... The high pressure wedge will attempt to break down and lift away as a warm front lifts toward the Mid-Atlantic ahead of low pressure over the Midwest. Milder temperatures are expected as a result Friday into Saturday. As low pressure approaches, forcing for ascent will increase. Broad troughing aloft attendant to the surface low will scoot across the region through early Saturday resulting in widespread rain, albeit light. Amounts of 0.10-0.25" are expected with locally higher amounts possible in the terrain. Although showers are possible with the warm front lifting through during the day Friday, more widespread rain is expected Friday night as the low makes its closest approach. The system`s cold front will move through early Saturday. This should bring the threat of rain to an end by roughly midday for most of the region. Temperatures will again be mild as cold advection behind the front is weak and lags a bit. Northerly winds and clearing skies should bring temperatures down into the 20s and 30s Saturday night with dry conditions. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... Broad upper-level troughing pivots off the East Coast Sunday and Monday ahead of a ridge moving overhead Tuesday. At the surface, high pressure builds over the Mid-Atlantic Sunday through Monday morning ahead of a cold front pushing through the forecast area Monday afternoon. A low pressure system tracking across the Great Lakes from the central Plains pushes the associated frontal systems through the forecast area Wednesday. Dry conditions are expected Sunday through Monday morning with high pressure in place. Precipitation chances begin increasing along the Alleghenies Monday afternoon as the aforementioned cold front approaches from the northwest. Precipitation chances overspread the area Tuesday and linger through Wednesday. Overall, beneficial rain showers are expected Tuesday with showers becoming more isolated in nature on Wednesday. High temperatures will be in the 50s and 60s each day with highest elevations staying in the upper 40s. Overnight low temperatures drop into the 30s and 40s each night. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... MVFR CIGs will likely persist well into the daylight hours today, possibly lingering into the afternoon in spots. Light onshore flow will shift from NE to SE today. The change in wind direction may help weaken the subsidence inversion aloft a bit resulting in a general gradual lifting and scattering of lower clouds through the day. However, this will also be bringing in more moisture, which may have the opposite effect at times. AMDs will likely be necessary to capture near term/localized trends. For CHO and MRB, a period of IFR is likely this morning given some moisture pooling and lighter flow in the lowest 1 km AGL near these terminals. Mainly cloudy conditions will linger tonight. The increased low-level moisture from today`s light onshore flow with possible cloud breaks could lead to instances of fog. Certainty on fog development and magnitude is low given the chance for a lingering light wind and cloud cover. Winds shift to S Friday as a warm front lifts through. Some sub-VFR conditions are possible in lower CIGs and -RA at times. Low pressure and its cold front will follow Friday night into Saturday with increasing potential for lower CIGs and VSBYs due to more widespread rain through early Saturday morning. VFR is expected to return by Saturday afternoon as the cold front moves away and drier air moves in. VFR conditions are expected Sunday and Monday as high pressure builds over the region. Light southerly winds around 5 knots on Sunday shift to westerly on Monday, increasing slightly to 5 to 10 knots in the afternoon. && .MARINE... Light north to northeast flow is expected through this morning, becoming more southeasterly this afternoon. Dry but cloudy weather is expected through tonight. Winds shift to southerly Friday as a warm front lifts through. This warm front may bring a few rain showers. An area of low pressure and its associated cold front will glide across the area Friday night into early Saturday bringing more widespread rain. Winds may increase out of the south for a time ahead of the low late Friday, then increase a bit more readily in the wake of the cold front Saturday. SCAs are possible late Friday through Saturday before winds become lighter under building high pressure Saturday night. Surface high pressure builds over the waters Sunday and Monday. Southerly winds on Sunday shift to westerly on Monday with winds expected to stay below SCA criteria. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...None. && $$ SYNOPSIS...DHOF/EST NEAR TERM...DHOF SHORT TERM...DHOF LONG TERM...AVS AVIATION...AVS/DHOF MARINE...AVS/DHOF